Emergency warning signal



FIG. 1 is a perspective view of an emergency warning signal showing mynew design;

FIG. 2 is a front elevational thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a rear elevational thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a right side elevational thereof; and,

FIG. 7 is a left side elevational view thereof.

The ornamental design for emergency warning signal, as shown anddescribed.